Diarrhoeal diseases
• 88% diarrhoael deaths worldwide from unsafe water, inadequate sanitation and poor hygiene
• 2nd killer of children under 5 globally (> than AIDS + malaria + measles) • Responsible for 11.0% of under 5 deaths in SA
• Persistent diarrhoea associated with an 11-fold
increase in mortality for children with HIV
Local helminthic infections
Study Ascaris lumbricoides
Trichuris trichiura
KZN health facilities (5 733 samples, Kwitshana et al, 2008)
11% 7%
Children in Durban slum (996 subjects, Appleton et al, 2008)
89% 71%
Improved sanitation (UD) in eThekwini (120 UD toilets, Trönnberg et al 2010)
59% 48%
Ascaris lumbricoides
• often asymptomatic
• Ascariasis: nutritional deficiencies, blockages by masses of worms
• eggs extremely resistant to treatment processes – useful as marker
• eggs bond to particles of soil and are not easily washed away; attach strongly to surfaces.
Trichuris trichiura
• + 1 billion people infected worldwide • prevalence may be as high as 95% among
children in some parts of the world • Light infections are often asymptomic • Heavy infections may result in Trichuris Dysentery
Syndrome (chronic dysentery, rectal prolapse, anaemia, poor growth)
• Children with heavy infections can become severely anaemic and growth-retarded developmental and cognitive deficits
Taenia solium • Burden of disease is possibly twice as high in Eastern Cape
than other parts of South Africa (Mafojane et al, 2003).
• A 2004 study found the burden of disease for the Eastern Cape alone to be between USD 18-34 million per annum; epilepsy accounted for the largest overall impact (Carabin et al, 2006).
• The free ranging of pigs, poor sanitation and lack of knowledge among the public about modes of transmission combine to make disease reduction a challenge
• Seventy-six percent of respondents in one study reported having seen cysts in the pork that they ate; only 80% knew what the cysts were (Carabin et al, 2006).
INTERVENTION:
Improve sanitation: put a safe distance
between us and our faeces
break the faecal-oral transmission
of disease
YES, BUT ….
Improved sanitation is often onsite
Onsite systems get full
When systems get full they have to be emptied
When they get emptied things get
messy
When things get messy the gains of
improved sanitation may be
reversed (or worse)
Awareness of sludge as hazardous material is not adequately reflected in policy and practice
“public works” approach rather than
“biohazard” approach
Awareness of risks to householders during servicing of onsite sanitation is inadequate
Improved sanitation for health benefits
ends with provision of a toilet
• Sludge remains highly pathogenic even after years in the pit
• There is no guarantee that helminth eggs will deactivate in sludge over
time
• Large numbers of Ascaris lumbricoides, Trichuris trichiura and Taenia solium have been recovered from the face masks of pit emptiers
• Viable ova left on hands of waste handler: Mean- 90; Max-2 300
• 100% risk of helminth infection for workers -- use of multiple barriers (gloves, hand washing with soap) reduces risk, does not eliminate it
• Bucket washers -- both their PPE gloves and their hands heavily contaminated. Bacterial counts from the hands of some workers upon reporting for work in the morning showed high levels of contamination not originating from their jobs
Sanitation workers have higher exposure to the pathogens found in sludge than the general public and may be at greater risk for infection.
Or are they?
Pit / septic tank emptiers may be at the greatest risk (raw sludge and on-site work conditions).
SITUATION
Splashes
Inhaling dust or aerosols
Eating and smoking
Contaminated protective gear
Transport of sludge and equipment
Care of tools and equipment
PROTOCOLS SHOULD ADDRESS:
• Donning/removing contaminated protective gear
• Situations where equipment cannot be coupled/decoupled while wearing gloves
• Accidents where hands, face or clothing come into direct contact with sludge
• Safe transport and cleaning of clothing, boots, bins, tools and equipment in order to prevent contamination of walkways and vehicles and to prevent workers from carrying pathogens home on their clothing
• Provision of immunizations and 6 monthly deworming treatments for all workers
It is equally important that pit emptiers be trained to protect the household environment of the families whose pits they empty
• During servicing of UD toilets:
• sludge was left exposed at the site in 72% cases • Viable ova left on the ground around emptying site Mean: 8 500 Max: 184 000
• None of the households marked the burial area • (84% of cases in close proximity to human activity)
• Only 12% left the area alone
Other sources of contamination?
Households with unimproved pit latrines in Tanzania: • Floors of homes were more highly
contaminated than the floors of latrines. • Surfaces in and around home -- soil, floors,
walls, cups and vegetables -- widely contaminated with faecal pathogens.
SITUATIONS
Spilling, spraying household surfaces
Dust
Washing contaminated equipment/hands at household tap
Using household tools
Tracking sludge on boots
The level of exposure to pathogens during sanitation work is related to a number of different factors
Policy and enforcement
Knowledge and attitudes
Procedures and protocols
Safety doesn’t begin and end with PPE
Interventions require resources
and must therefore be strategic
in order to be feasible
Oblivious
Aware
Willing
Implementing
BARRIERS TO BARRIERS
• Lack of resources
• Lack of education/awareness
• Desensitizaton
• “Public works” mentality
• Lack of policy
• Lack of procedure/protocol
• Lack of monitoring/supervision/enforcement
FURTHER INVESTIGATIONS
POLICY REVIEW
ATTITUDES, BELIEFS,BEHAVIOURS
INTERVIEWS AND OBSERVATIONS
VIABILITY OF PATHOGENS
EFFICACY OF DISINFECTANTS
GAPS AND RELATIONSHIPS
Thanks to
Nicola Rodda, UKZN
Colleen Archer, PRG, UKZN
eThekwini Municipality
Steven Sugden, Water for people
for photos and resources
REFERENCES
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